Electronic communication system

ABSTRACT

In order to develop an electronic communication system ( 100; 100′ ), designed for a progressive movement means, having at least one base station ( 10 ) and having at least one carrier station ( 60 ) such that the possible uses of this communication system ( 100; 100′ ) can also be extended to other important areas of use of a progressive movement means, it is proposed that the carrier station ( 60 ) be designed as in each case at least one sensor unit, which is assigned to at least one wheel or tire ( 90 ) of the progressive movement means and—which is designed to detect and/or determine at least one characteristic parameter of the wheel or tire ( 90 ), such as for example the air pressure and/or the temperature and/or the wear of the wheel or tire ( 90 ).

The present invention relates in general to the technical field ofelectronic circuits and the design of the physical layout thereof.

Specifically, the present invention relates to an electroniccommunication system for a progressive movement means as claimed in theprecharacterizing clause of the main claim.

An electronic communication system of the type mentioned above is knownfrom the document WO 00/15931 A1.

However, said communication system is limited in its applicationpossibilities in that it is designed essentially for the keyless lockingand opening of the doors of a progressive movement means. In conjunctiontherewith, the known subject matter according to the document WO00/15931 A1 allows merely an exchange of data and signals between a basestation and a data carrier that is designed, for example, in the form ofa card.

Since, however, nowadays increased demands are being placed in theautomobile sector on the function and the reliability of certaincomponents, the proposed solution according to the document WO 00/15931A1 no longer appears to be entirely satisfactory.

Starting from the above-described disadvantages and shortcomings and inacknowledgement of the outlined prior art, it is an object of thepresent invention to develop an electronic communication system of thetype mentioned above such that the possible uses of this communicationsystem can also be extended to other important areas of use of aprogressive movement means.

This object is achieved by an electronic communication system having thefeatures given in claim 1. Advantageous refinements and expedientdevelopments of the present invention are characterized in thesubclaims.

According to the teaching of the present invention, the communicationbetween the base station and the sensor unit that is assigned to atleast one wheel or tire of the progressive movement means is effectedcapacitively; the sensor unit in this case serves to detect and/ordetermine at least one characteristic parameter of the wheel or tire,such as for example the air pressure and/or the temperature and/or thewear of the wheel or tire. The detected or determined data are thencapacitively exchanged with the base station using signal technology.

The present invention hereby differs substantially from conventionalarrangements in which, in order to effect communication between the basestation and the associated sensors located on the wheel or in the tire,a configuration is usually used which is based on an inductive principleand is shown in FIG. 1, which is to be ascribed to the prior art:

In the case of this inductive coupling according to the prior art, whatis referred to as the base station B (having an U[ltra]H[igh]F[requency]receiver B.1, a microcontroller B.2 and a L[ow]F[requency] transmitterB.3) with the respective inductive antennas B.4.1, B.4.2, B.4.3 andB.4.4 that are designed in the form of coils (having an associatedmultiplexer or having four associated transmitters B.4) initiates acommunication sequence for the deliberate selective activation (what isreferred to as the “inductive wake-up 1, 2, 3, 4”) of the respectivesensor circuit S (having an active L[ow]F[requency] receiver S.1, amicrocontroller S.2 and an U[ltra]H[igh]F[requency] transmitter S.3 forthe “UHF response” to the U[ltra]H[igh]F[requency] receiver B.1); theactivation of the sensor electronics is hereby effected over at leastone inductive channel.

However, on account of the system, this type of inductive datatransmission holds some problems and risks in that the magnetic fieldbetween the transmitting antenna and the receiving antenna is screenedin unfavorable orientations by the rim of the wheel or tire; althoughsuch an undesirable screening can in some circumstances be preventedusing a number of coils on the base station and/or on the sensor, atechnical measure such as this is naturally cost-intensive.

Furthermore, in inductive coupling it has been proven that the influenceof metal is problematic in that the metal in the vicinity of theinductive communication system leads to an influencing of the fieldcharacteristic and thus possibly to positions at which communication isno longer possible. In this connection, the metal parts located in thevicinity of the transmitting coils and the metal parts located in thevicinity of the receiving coils also lead to a detuning of the resonantcircuit, which in turn brings about a reduction in the radiated fieldand also a decrease in the voltage on the resonant circuit at thereceiver side.

Finally, in the case of the inductive coupling of base station andsensor unit(s), the magnetic field may be damped by eddy currents onaccount of the increasing use of conductive tire rubber, as a result ofwhich communication problems may likewise arise in some circumstances.

By a capacitive coupling principle now being proposed according to theinvention for communication between base station and sensor unit(s),compared with the previously known inductive coupling principle a numberof advantages can be achieved:

Since inductive coupling is dispensed with, a large number of coils bothon the base station and on the sensor electronics can be saved, as aresult of which a large reduction in costs is achieved. Besidesdispensing with (ferrite) coils, capacitive-based coupling also makes itpossible for additional savings to be made, both in terms of theelectronics of the base station and in terms of the electronics of thesensors located on the wheel or in the tire, as a result of which thecosts can be further reduced.

In the present invention, it is also advantageous that cost-effectiveimplementation possibilities for the electrodes makes the use thereof inmass production beneficial; in principle, the mechanical arrangement ofthe transmitter electrode (=coupling electrode of the base station) andof the receiver electrode (=coupling electrode of the sensor unit) canin this case be selected at will.

A practical implementation of the electrode arrangement in simplemechanical configurations is also possible, where the capacitivecoupling electrodes can be mechanically matched, in a very simplemanner, to the conditions of the respective vehicle platform, and canalso be designed to be much more stable in mechanical terms than themechanically and thermally sensitive (ferrite) coils that are necessaryfor inductive communication.

The person skilled in the art in the field of communication electronicsfor progressive movement means, for example an electrical engineer withextensive knowledge in the field of motor vehicle electronics, withreference to the present invention will be able to appreciate that thecommunication conditions are no longer dependent on the position—as theywere in the case of inductive solutions—since the coupling capacitanceis approximately constant even during the rotation of the wheel or tire.This property allows reliable communication even at high speeds of theprogressive movement means of more than 200 kilometers per hour.

The last-mentioned aspect also not least adds to the huge gain in activereliability and also passive reliability, which is made possible by thepresent invention, compared with inductive couplings; this extrareliability is already very highly valued in relation to wheels andtires of a progressive movement means; however, a burst wheel or tire athigh speed can, for example, lead to traffic accidents with seriousinjuries and/or fatal consequences.

According to a particularly advantageous refinement of the presentinvention, the carrier station, in particular the coupling electrode ofthe carrier station, can be spatially assigned to the valve of the wheelor tire of the progressive movement means and/or be electricallyinsulated from the rim of the wheel or tire of the progressive movementmeans; accordingly, the coupling electrode of the sensor unit can belocated on the wheel or tire.

Such a refinement is useful, for example, in the case of frameworkconditions in which the steel belt of modern tires is partially replacedby electrically non-conductive reinforcements and/or is not closed, sothat such a steel belt can in some circumstances not always be used asan “auxiliary electrode”.

For practical reasons (for example simple mounting and effectiveservicing) and/or for reasons of cost, too, it may prove to beadvantageous for the coupling electrode (what is referred to as the“receiver electrode”) and the carrier station (what is referred to asthe sensor unit or “tag”) where possible to be combined in a singlemodule; in other words, this means that the carrier station and thecoupling electrode can be designed as a single component and/or as aone-piece module.

In order, in this connection, to take other considerations andlaboratory studies into account, a connection or fusion of the carrierstation and/or of the coupling electrode to the valve of the wheel ortire may prove to be expedient, that is to say that the carrier stationand/or the coupling electrode may be mechanically integrated in thevalve body of the wheel or tire, so that the valve, the couplingelectrode and possibly also the carrier station (=the sensor unit) forma single component.

The preferred refinements given above, in relation to which the priorart contains a number of constructive indications relating to theconnection of antennas for tire sensor circuits to the valve body of thetire, for instance

-   -   from the document DE 1 048 195

(control member for monitoring the tire pressure can be fitted to thevalve, connect a contact to the rim and be capacitively coupled tocorresponding electrodes on the vehicle body),

-   -   from the document U.S. Pat. No. 3,249,916

(valve shaft comprises pressure indicator),

-   -   from the document JP 11-180117

(assembly combined with the tire valve for monitoring the tire pressure,where the valve shaft also bears a coil-shaped antenna which is screwedonto the outside of the valve shaft; the assembly comprises a pressuresensor, a signal processing circuit and a battery) or

-   -   from the document JP 2000-052726

(assembly combined with the tire valve for monitoring the tire pressure,where the valve shaft also serves as antenna; the assembly comprises amicroprocessor and a battery), have a number of advantages, forinstance, among other things, the combining of the coupling electrode(what is referred to as the “receiver electrode”) and the carrierstation (what is referred to as the sensor unit or “tag”) in a singlemodule, which makes mounting and servicing considerably easier.

Furthermore, simple mechanical integration of the coupling electrodeinto the existing valve is also possible, where the proposed refinementscan be used both with steel breaker tires and with metal-free tires.Possibilities for making the electrodes in a cost-effective manner makethe method beneficial for use in mass production.

According to embodiments of the present electronic communication systemthat are essential to the invention, there may be provided

-   -   a bidirectional capacitive connection with bidirectional        capacitive data transmission or    -   a unidirectional capacitive connection with        U[ltra]H[igh]F[requency] response.

The present invention, which incorporates both at least one base stationof the type mentioned above and at least one sensor unit of the typementioned above, can be used advantageously in progressive movementmeans, in particular in motor vehicles, in which sensors are used whichare located in the wheels or tires. In order to achieve the necessaryservice life of the battery, these sensors carry out measurements onlyperiodically and are assigned to a specific wheel or tire on the vehicleside.

For this, the sensors are selectively addressed or woken up in asuitable manner (what is referred to as the “wake-up”). For thispurpose, the base station initiates a communication sequence for thedeliberate, selective activation of the respective sensor circuit, wherethe activation of the sensor electronics is effected according to theinvention over at least one capacitive transmission channel.

Typical sensors for which the present arrangement can advantageously beused are, for example,

-   -   wheel pressure sensors or tire pressure sensors,    -   wheel temperature sensors or tire temperature sensors, or    -   wheel wear sensors or tire wear sensors;        the present invention also relates to the use of at least one        capacitive coupling for data communication between at least one        base station and at least one wheel or tire.

Now that the advantages of an electronic communication system on acapacitive basis have been explained above, at this point it should bepointed out that—in addition to the document WO 00/15931 A1 discussedabove—the document WO 96/36134 A1 also discloses a wireless system thatcomprises a transmitter and a receiver which, however, are coupledthrough a user and through the ground potential of a room. Thetransmitter generates low-frequency signals of low power, which flow bycapacitive coupling as displacement currents through the body of theuser. The distributed ground potential of the room acts as return pathfor the current.

Furthermore, it should be mentioned that the document EP 0 843 425 A2discloses an electronic communication device which uses the human bodyas a transmission medium. This conventional communication device is usedto encrypt and transmit data from a transmitter, which may preferably bedesigned as a card, to a receiver, which is preferably contained in abase station.

The transmitter according to the document EP 0 843 425 A2 comprises agenerator for generating an electric field, a data encryption device,which becomes active by modulation of the electric field, andelectrodes, in order to couple the electric field through the humanbody. The receiver according to the document EP 0 843 425 A2 compriseselectrodes which are in physical contact with or in close proximity topart of the human body, in order to detect an electric field which istransmitted through the body.

A demodulator within the receiver extracts the data from the modulatedelectric field. It is also stated that a receiver electrode can bearranged in a metal door handle of a motor vehicle. The doors will beunlocked automatically when the holder of an authorized card, that is tosay an authorized transmitter, touches the door handle with his hand.Touching of the door handle without pulling the latter for a certainperiod of time, for example fifteen seconds, brings about unlocking ofall the doors.

As explained above, there are various possibilities for refining anddeveloping the teaching of the present invention. For this purpose, onthe one hand, reference is made to the claims that are dependent onclaim 1 and, on the other hand, the invention will be further describedwith reference to examples of embodiment shown in the drawings to which,however, the invention is not restricted.

FIG. 1 schematically shows the communication principle, based oninductive coupling, between a base station and an associated sensor unitin the form of a sensor located in the tire or on the wheel, accordingto an example of embodiment of the prior art;

FIG. 2 schematically shows the electrical circuit diagram of thecapacitive data transmission in the case of the communication principle,based on capacitive coupling, between a base station and an associatedsensor unit in the form of a sensor located in the tire (cf. FIG. 3) oron the wheel (cf. FIG. 4), according to the present invention;

FIG. 3 schematically shows, in section, the communication principle ofFIG. 2 according to a first mechanically designed example of embodimentof the present invention; and

FIG. 4 shows, in a partially cut-away perspective view, thecommunication principle of FIG. 2 according to a second mechanicallydesigned example of embodiment of the present invention.

Arrangements, elements or features that are identical or similar bearthe same references in FIGS. 2 to 4.

As shown schematically in principle in FIG. 2 and also in FIG. 3 on thebasis of a first mechanically designed example of embodiment and in FIG.4 on the basis of a second mechanically designed example of embodiment,the basic idea of the present invention is to use, instead of inductivedata transmission as shown in FIG. 1 according to the prior art, withinthe context of an electronic communication system 100 (cf. FIG. 3) or100′ (cf. FIG. 4), advantageously a capacitive transmission channel fordata transmission between a base station 10 and a carrier station 60.

The carrier station is in this case designed, in a manner essential tothe invention, as a sensor unit 60 assigned to a wheel or tire 90 of amotor vehicle, and serves to detect and determine characteristicparameters of the wheel or tire 90, namely the air pressure, thetemperature and the wear of the wheel or tire 90.

For this purpose, a capacitive connection 50 is produced between acoupling electrode 12 of the base station 10, which is designed astransmitter electrode, and a coupling electrode 62 of the sensor unit60, which is designed as receiver electrode; this capacitive connectionfor the transmission of data signals is shown symbolically in FIG. 2 bya coupling path 50 that is equivalent to a coupling capacitor and inFIG. 3 by a coupling capacitor 50 that symbolizes the coupling path andis formed by the coupling electrode 12 of the base station 10 and by thecoupling electrode 62 of the sensor unit 60.

FIG. 2 then shows, in principle, the circuit design, used for the firstexample of embodiment according to FIG. 3 and also for the secondexample of embodiment according to FIG. 4, of the base station 10 and ofthe sensor unit 60, where this circuit is designed for unidirectionaldata transmission from the base station 10 to the sensor unit 60.

In this example of embodiment, the data signal processing circuit 20assigned to the base station 10 comprises an inductance 22 that isoptionally provided with at least one screen 32, a capacitance 24 and adriver circuit 26 in the form of a modulator; these elements 22, 24 and26 are connected in series with one another. The coupling electrode 12of the base station 10 is connected at the connection point 28 betweenthe inductance 22 and the capacitance 24, and the ground electrode 14 ofthe base station 10 is connected at the connection point 30 between thecapacitance 24 and the driver circuit 26.

In a comparable manner, the data signal processing circuit 70 assignedto the sensor unit 60 and in particular in this case to the rim 94 (cf.FIGS. 3 and 4) comprises a resonant circuit, which comprises aninductance 72 and a capacitance 74, and also a driver circuit 76 in theform of a demodulator. This demodulator 76 serves to demodulate receiveddata signals, and also to process them. The inductance 72 and thecapacitance 74 form a parallel resonant circuit which is connected tothe demodulator 76. The coupling electrode 62 of the sensor unit 60 isfurthermore connected at the connection point 78 between the inductance72, the capacitance 74 and the demodulator 76. The ground electrode 64of the sensor unit 60 is connected at the other connection point 80between the inductance 72, the capacitance 74 and the demodulator 76.

The precise coupling of the ground electrode 14 of the base station 10,the coupling electrode 12 of the base station 10, the coupling electrode62 of the sensor unit 60 and the ground electrode 64 of the sensor unit60 via the capacitive connection 50 and also via the electrical, that isto say ohmic or likewise capacitive, connections 52 (=assigned to thebase station 10) and 54 (=assigned to the sensor unit 60) are explainedbelow with reference to FIG. 3.

In the real system of the first example of embodiment according to FIG.3, there is an electric field between the coupling electrode 12 of thebase station 10, which is designed as the transmitter electrode, and thesteel reinforcement of the outer case 92 of the wheel or tire 90 andalso between this steel reinforcement and the coupling electrode 62 ofthe sensor unit 60, which is designed as the receiver electrode. Theelectrical circuit is connected via the electrically or likewisecapacitively coupled connection between the electronics of the basestation 10 and the electronics of the sensor unit 60 (metallic partsbetween wheel guard 40 and rim 94 of the wheel or tire 90, where thewheel guard 40 and the rim 94 are optionally electrically connected toone another).

In this case, the coupling between the vehicle-side base station 10 andthe sensor 60 located in the tire (cf. FIG. 3) or on the wheel (cf. FIG.4) can be seen, for example, in detail below:

The capacitive transmitter 10 is electrically connected at one pole tothe transmitter electrode 12 in the wheel guard 40. This transmitterelectrode 12 capacitively couples to the steel reinforcement in thewheel or tire 90. This in turn is electrically or likewise capacitivelyconnected to a receiver electrode 62 of the sensor 60. In the sensor 60there is an electrical connection to the second sensor electrode 64.

This second sensor electrode 64 in turn is electrically or likewisecapacitively connected to the rim 94. The rim 94 is electrically (viathe wheel bearing) or capacitively connected to the vehicle chassis. Thevehicle chassis in turn is electrically connected to the second pole ofthe base station. There is thus a closed electrical circuit which iscarried partly via conductive currents and partly via capacitivedisplacement currents.

With respect to the practical arrangement of the electroniccommunication system 100 outlined above by way of example, it seemsparticularly noteworthy that the function of this capacitivecommunication system 100 is still provided even when the transmitterelectrode 12 in the wheel guard 40 is around two meters away from thesteel reinforcement of the wheel or tire 90; in view of the fact thatthis distance is in practice only around twenty centimeters, thecapability of the proposed principle is also not least documented by thefact that ten times the electrode distance (from twenty centimeters totwo meters) leads to a reduction in the available electric field byaround a factor of 100, since this electric field strength decreases bythe square of the electrode distance.

Using this capacitive connection 50, it is now possible for example towake up the sensor electronics of a specific wheel or tire 90 via afreely selectable protocol, and thus to trigger a measurement operation.The transmission return channel from the sensor unit 60 to the basestation 10 can likewise be designed in a capacitive manner or else useany other transmission channel; in the latter case, for instance, aunidirectional capacitive connection from the base station 10 to thesensor unit 60 can be effected using an U[ltra]H[igh]F[requency]response of the wheel or tire parameter values, detected or determinedby the sensor unit 60, to the base station 10.

The real system of the second example of embodiment for a capacitivecommunication system 100′ according to FIG. 4 relates in particular tothe constructive arrangement of the wheel or tire electrode, that is tosay the coupling electrode 62 of the carrier station 60, for effectingcapacitive communication between the base station 10 and the wheelsensor or sensors, that is to say the sensor station 60.

Accordingly, the second example of embodiment according to FIG. 4differs from the first example of embodiment according to FIG. 3 aboveall in that the coupling electrode 62 of the sensor unit 60 is locatedon rather than in the wheel or tire 90.

One reason for this variation with respect to the first example ofembodiment according to FIG. 3 is, inter alia, that framework conditionscan be defined in which the steel belt of modern tires 90 is in somecircumstances partially replaced by electrically non-conductivereinforcements and/or is not closed, so that such a steel belt can insome circumstances not always be used as an “auxiliary electrode”.

For practical reasons (for example simple mounting and effectiveservicing) and/or for reasons of cost, too, it may prove to beadvantageous for the coupling electrode 62 (what is referred to as the“receiver electrode”) and the carrier station 60 (what is referred to asthe sensor unit or “tag”) where possible to be combined in a singlemodule, as shown in the second example of embodiment according to FIG.4.

In order, in this connection, to take other considerations andlaboratory studies into account, in the second example of embodimentaccording to FIG. 4 the coupling electrode 62 is fused to the valve 96of the wheel or tire 90, that is to say that the coupling electrode 62is mechanically integrated in the valve body 96 of the wheel or tire 90.

As shown in the electrical circuit diagram in FIG. 2 and also in thefirst example of embodiment according to FIG. 3, the coupling electrode62 is electrically or capacitively connected to the electronics of thesensor unit 60. Furthermore, this capacitive coupling electrode 62 iselectrically insulated with respect to the wheel rim, that is to saywith respect to ground.

The sensor unit 60 is connected to the wheel rim, that is to say toground, by means of its second terminal, that is to say electrically bymeans of its ground electrode 64 or capacitively in FIG. 4, as shown inthe electrical circuit diagram of FIG. 2 and in the first example ofembodiment according to FIG. 3.

The second example of embodiment according to FIG. 4 has a number ofadvantages, for instance, among other things, the combining of thecoupling electrode 62 (what is referred to as the “receiver electrode”)and the carrier station 60 (what is referred to as the sensor unit or“tag”) in a single module, which makes mounting and servicingconsiderably easier.

Furthermore, in the second example of embodiment according to FIG. 4,simple mechanical integration of the coupling electrode 62 into theexisting valve 96 is also possible, where the disclosed embodiment canbe used both with steel breaker tires and with metal-free tires.Possibilities for making the electrodes 62, 64 in a cost-effectivemanner make the method beneficial for use in mass production.

Where in the text above corresponding explanations in relation to thesecond example of embodiment of the capacitive communication system 100′according to FIG. 4 have not been given, reference is made to thecorresponding explanations in relation to the first example ofembodiment of the electronic communication system 100 according to FIG.3, for the purpose of avoiding unnecessary repetitions in relation tothe arrangements, elements, features and/or advantages of the secondexample of embodiment according to FIG. 4; these arrangements, elements,features and/or advantages of the first example of embodiment accordingto FIG. 3 are—unless indicated otherwise in the second example ofembodiment according to FIG. 4—expressly given in relation to thesubject of the explanations regarding the second example of embodimentof the electronic communication system 100′ according to FIG. 4.

Finally, with respect to the two examples of embodiment of the presentinvention shown in FIGS. 2 to 4, it should be pointed out that these twoexamples of embodiment according to the invention also allow abidirectional capacitive connection with bidirectional capacitive datatransmission, for instance by both the driver circuit 26 assigned to thebase station 10 and the driver circuit 76 assigned to the sensor unit 60being designed in each case as a combined modulator/demodulator unit.

If the capacitive communication is bidirectional, the coupling electrode62 can accordingly be designed as the receiver electrode and/or as thetransmitter electrode.

LIST OF REFERENCES

-   100 electronic communication system (first example of embodiment    according to FIG. 3)-   100′ electronic communication system (second example of embodiment    according to FIG. 4)-   10 base station-   12 coupling electrode of the base station 10-   14 ground electrode of the base station 10-   20 processing circuit of the base station 10-   22 inductance of the processing circuit 20-   24 capacitance of the processing circuit 20-   26 driver circuit, in particular modulator, of the processing    circuit 20-   28 connection point between inductance 22 and capacitance 24-   30 connection point between capacitance 24 and driver circuit 26-   32 Screen of the inductance 22-   40 wheel guard-   50 first coupling path between base station 10 and sensor unit 60,    in particular coupling capacitor formed by coupling electrode 12 of    the base station 10 and by coupling electrode 62 of the sensor unit    60-   52 second coupling path between base station 10 and sensor unit 60,    in particular coupling capacitor formed by ground electrode 14 of    the base station 10 and by ground potential-   54 third coupling path between base station 10 and sensor unit 60,    in particular coupling capacitor formed by ground electrode 64 of    the sensor unit 60 and by ground potential-   60 carrier station =sensor unit-   62 coupling electrode of the sensor unit 60-   64 ground electrode of the sensor unit 60-   70 processing circuit of the sensor unit 60-   72 inductance of the processing circuit 70-   74 capacitance of the processing circuit 70-   76 driver circuit, in particular demodulator, of the processing    circuit 70-   78 first connection point between inductance 72, capacitance 74 and    driver circuit 76-   80 second connection point between inductance 72, capacitance 74 and    driver circuit 76-   90 wheel or tire-   92 outer case of the wheel or tire 90-   94 rim of the wheel or tire 90-   96 valve of the wheel or tire 90

1. An electronic communication system for a progressive movement means,having at least one base station arranged in the progressive movementmeans and at least one carrier station, in particular a movable carrierstation, that is designed to exchange data signals with the basestation, where the base station has at least one coupling electrode, atleast one ground electrode and at least one processing circuit fortransmitting and/or receiving the data signals, formed by a voltagebetween the coupling electrode and the ground electrode, between thecarrier station and where the carrier station has at least one couplingelectrode, at least one ground electrode and at least one processingcircuit for receiving and transmitting the data signals, formed by avoltage between the coupling electrode and the ground electrode, betweenthe base station, where the coupling electrode of the base station andthe coupling electrode of the carrier station are coupled to one anotherduring operation via a coupling path for the transmission of the datasignals, which coupling path has at least one capacitive connectionprovided over at least one electric field, where the ground electrode ofthe base station is connected electrically or capacitively duringoperation to an electrical ground body of the progressive movement meansand where the ground electrode of the carrier station is connectedelectrically or capacitively during operation to the electrical groundbody of the progressive movement means, characterized in that thecarrier station is designed as in each case at least one sensor unit,which is assigned to at least one wheel or tire of the progressivemovement means and which is designed to detect and/or determine at leastone characteristic parameter of the wheel or tire.
 2. A communicationsystem as claimed in claim 1, characterized in that the carrier station,is spatially assigned to the outer case or the valve of the wheel ortire of the progressive movement means and is electrically insulatedfrom the rim of the wheel or tire of the progressive movement means. 3.A communication system as claimed in claim 2, characterized in that thecarrier station and/or the coupling electrode are integrated in thevalve of the wheel or tire.
 4. A communication system as claimed inclaim 1, characterized in that the carrier station and the couplingelectrode are designed as a single component and/or as a one-piecemodule.
 5. A communication system as claimed in claim 1, characterizedin that the coupling electrode of the base station is spatially assignedto the wheel guard of the progressive movement means and is electricallyinsulated from the wheel guard.
 6. A communication system as claimed inclaim 1, characterized in that the processing circuit of the basestation has at least one inductance, at least one capacitance and atleast one driver circuit in the form of at least one modulator, whichare preferably connected to one another in series, where the couplingelectrode of the base station is preferably connected at the connectionpoint between the inductance and the capacitance and/or where the groundelectrode of the base station is preferably connected at the connectionpoint between the capacitance and the driver circuit.
 7. A communicationsystem as claimed in claim 1, characterized in that the processingcircuit of the carrier station has at least one inductance and at leastone capacitance, which are preferably connected to one another inparallel as a resonant circuit, and also at least one driver circuit inthe form of at least one demodulator, where the coupling electrode ofthe carrier station is preferably connected at the connection pointbetween the inductance, the capacitance and the driver circuit and/orwhere the ground electrode of the carrier station is preferablyconnected at the other connection point between the inductance, thecapacitance and the driver circuit.
 8. A base station for an electroniccommunication system as claimed in claim
 1. 9. A sensor unit for anelectronic communication system as claimed in claim
 1. 10. The use of atleast one electronic communication system as claimed in claim 9, fordetecting and/or determining at least one characteristic parameter.